Digital Signatures
Abstract:
A fixed length signature is appended onto the message using a 256 bit hash (SHA256) which would represent the senders private key, and the receiver then takes the hash of the message it receives, and decrypts using the public key.
As the signature is created from a hash of the message and encrypted with a private key, that means if someone changed the message, they wouldn’t have the private key to re-encrypt the digital signature and as the receiver knows the genuine public key, they would be able to tell that the message had been altered.